I’m preparing for the next semester at the university starting in September this year. As part of that, I’m currently evaluating the Freescale Kinetis FRDM-KL43Z board:

FRDM-KL25Z, the most popular Freedom Board?

The Freescale FRDM-KL25Z board is used a lot, including in this blog when I first used that board back in September 2012: there are plenty of tutorials available, the board has the best price/performance ratio, and students including myself really love it. Freescale has later on released other FRDM boards with better features, but in my opinion they were simply too expensive and not well supported with examples and tutorials. I have monitored my board distributors on Mouser.com and Farnell/element14, and the number of available boards and the inventory fluktuations let me believe that indeed the FRDM-KL25Z is probably a high runner for them too. The FRDM-KL46Z would have been a good sucessor of the FRDM-KL25Z, but yet again, the price/performance ratio was not matching the KL25Z board: the FRDM-KL46Z was in the >$25 range 😦

Checking recently the price point of the FRDM-KL46Z, I noticed that it was now down to CHF 19, still 50% up to the CHF 12 for a FRDM-KL25Z. But at the same price as the FRDM-KL46Z I saw that there is a FRDM-KL43Z which I had not used yet. So I ordered two boards to explore it.

Package Content

The board comes as the other FRDM boards in a card box with a Quick Reference card, without USB cables and without headers populated:

Freedom Board Comparison

The picture below shows the three boards from left to right: FRDM-KL25Z, FRDM-KL43Z and FRDM-KL46Z:

	FRDM-KL25Z	FRDM-KL43Z	FRDM-KL46Z
Device	KL25Z128	KL43Z256	KL46Z256
Part	MKL25Z128VLK4	MKL43Z256VLH4	MKL46Z256VLL4
Package	LQFP, 80 pin	LQFP, 64pin	LQFP, 100 pin
ARM	Cortex-M0+	Cortex-M0+	Cortex-M0+
FLASH	128 Kbyte	256 Kbyte	256 Kbyte
SRAM	16 Kbyte	32 Kbyte	32 Kbyte
Max Speed	48 MHz	48 MHz	48 MHz
Push Button	no	2	2
Touch Slider	yes	yes	yes
LED	RGB	Green, Red	Green, Red
Accelerometer	MMA8451Q	MMA8451Q	MMA8451Q
Magnetometer	no	MAG3110	MAG3110
Light Sensor	no	Analog, ALS-PT19-315C/L177/TR8	Analog, ALS-PT19-315C/L177/TR8
Segment LCD	no	7-Segment, 4 digits	7-Segment, 4 digits
OpenSDA	P&E, V1	P&E, V1	P&E, V1
USB	yes, needs crystal	yes, crystal-less	yes, needs crystal
ROM Bootloader	no	yes	no
Processor Expert	full: LDD and SDK	partical: SDK only	full: LDD and SDK
Price (CHF)	12	19	19

So the FRDM-KL43Z is very similar to the FRDM-KL46Z, but around 50% more expensive than the FRDM-KL25Z.

💡 Check your local distributor prices, as I have found pricing Freedom boards very inconsistent, depending on distributor or local distributor web store!

Compared to the FRDM-KL25Z the KL43Z has more FLASH, more RAM, Magnetometer, 7-Segment LCD, push buttons and an ambient light sensor, and has a smaller package than the KL25Z (80 pins) and KL46Z (100 pins). Because of the less pins on the package, not all Arduino header pins on the side are connected.

An interesting feature I need to explore is the ROM bootloader present in the KL43Z. On the downside, the KL43Z is not fully supported any more with Processor Expert, making writing and porting applications to the KL43Z much harder or even impossible :-(.

Freescale Kinetis Design Studio Support

The FRDM-KL43Z is listed in Kinetis Design Studio, with Kinetis SDK v1.2 installed:

Processor Expert is only supported in combination with the Kinetis SDK:

So there is no LDD (Logical Device Drivers) support available for the KL43Z. That means that all the existing tutorials using Processor Expert for all the other boards will not work any more, projects cannot be easily ported and I have to start pretty much from scratch.

Summary

The FRDM-KL43Z is a new board, very comparable with the FRDM-KL46Z. On the plus side it comes with a ROM bootloader and crystal-less USB operation. On the downside I would have to rewrite all my existing applications for that new board. It is supported with Kinetis Design Studio (Segger and J-Link). So from that perspective the FRDM-KL46Z is better enabled than the KL43Z. If the price of the FRDM-KL43Z would get closer to the FRDM-KL25Z one, then the FRDM-KL43Z could be the next Freescale Freedom High-Runner board. The bit (potential) plus of the KL43Z in my view is the ROM bootloader, so I would like to explore this in one of my future articles.

Happy Evaluating 🙂

Links

• Freescale Freedom boards: http://www.freescale.com/freedom
• FRDM-KL43Z Board: http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=FRDM-KL43Z
• Freescale Kinetis Design Studio: http://www.freescale.com/kds
• Freescale Kinetis Bootloader: http://www.freescale.com/kboot